Wikipedia:Reference desk/Archives/Mathematics/2019 September 13

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September 13

Symmetrical set Venn diagram

(This work was licenced under CC BY-SA 3.0 License and the GFDL by theirs authors. Citation of the authors is given at the end of their text. ) Wow! It's amazing how you made Symmetrical 5-set Venn diagram ! May I ask you how you obtained it and if it's possible to use this how-to in order to make Symmetrical set Venn diagram with more than 5 sets, please. It would be very kind. 92.188.54.144 17:43, 24 August 2019 (UTC)

   Thanks! It was originally designed by mathematician Branko Grünbaum. I wrote the Python program at http://commons.wikimedia.org/wiki/File:Symmetrical_5-set_Venn_diagram.svg#Summary to make the smallest regions as large as possible. Let me know if you've other questions. Cheers, cmɢʟee ⋅τaʟκ 15:09, 25 August 2019 (UTC)

May I ask you if there is a way to obtain a 6-or-more by using a software ? Note : it's me the former called "92.188.54.144 17:43, 24 August 2019 (UTC)". My IP provider changes my ip adress any time.2A01:CB0C:38C:9F00:31CD:9270:5879:5FE6 16:41, 2 September 2019 (UTC)

   6-set Venn diagram SMIL.svg
   I don't know if a way to do that, but know of the above 6-set Venn diagram made of only triangles, devised by Jeremy J Carroll ( http://www.hpl.hp.com/techreports/2000/HPL-2000-73.pdf ). In the SVG, Hover over a set to highlight it, and click it to select and deselect it.
   Would it help to register an account so that you can have a permanent customisable identity? You needn't use your real name if you prefer not to. Cheers, cmɢʟee ⋅τaʟκ 00:18, 3 September 2019 (UTC)

I fact, I prefer ellipses. Furthermore, in this figure there are areas far too small.2A01:CB0C:38C:9F00:31CD:9270:5879:5FE6 00:25, 3 September 2019 (UTC)

   Me too. Sadly, I don't know of a way to generate them analytically. Would you like to post your question at en: Wikipedia:Reference_desk/Mathematics? Someone there may be able to answer it. Cheers, cmɢʟee ⋅τaʟκ 08:49, 4 September 2019 (UTC)

2A01:CB0C:38C:9F00:C1BA:AE9C:744:AACD (talk) 20:20, 12 September 2019 (UTC) I really wish a symetrical Venn diagram with the smallest areas as large as possible for n≥6.Is there a software to do that, please ? Thank you by advance .2A01:CB0C:38C:9F00:C1BA:AE9C:744:AACD (talk) 20:20, 12 September 2019 (UTC) . Note : it’s me the former 2A01:CB0C:38C:9F00:31CD:9270:5879:5FE6 and 92.188.54.144

You may need to go to 3 dimensions to get what you want (using an ellipsoid instead of ellipse). And you would want a 3D model you could rotate, and maybe turn some of the lobes off, to make it easier to visualize a particular intersection. Z-clipping could also help. Perhaps an animated GIF could be created that uses some of those techniques to highlight each intersection.

It poses an interesting math Q as to how many symmetrical Venn diagrams including every possible intersection could be made using all identical ellipsoids in 3D space. I'm thinking somewhere in the range of 8-20, but if someone knows how to mathematically figure this out, please do. SinisterLefty (talk) 21:17, 13 September 2019 (UTC)

Sphericity

If it is a concept, how is it defined? 86.8.200.155 (talk) 20:50, 13 September 2019 (UTC)

No, ignote, it's ok. Wikipedia has an article already.

86.8.200.155 (talk) 20:55, 13 September 2019 (UTC)

Resolved

SinisterLefty (talk) 21:05, 13 September 2019 (UTC)

Courtesy link: Sphericity. -- ToE 13:12, 14 September 2019 (UTC)